BARKETT, Justice.

We have for review In re Guardianship of Browning, 543 So.2d 258 (Fla. 2d DCA 1989), in which the district court certified the following question as one of great public importance:

Whether the guardian of a patient who is incompetent but not in a permanent vegetative state and who suffers from an incurable, but not terminal condition, may exercise the patient's right of self-determination to forego sustenance provided artificially by a nasogastric tube?

I. THE FACTS

On November 19, 1985, a competent Estelle Browning executed a declaration that provides, in part:

If at any time I should have a terminal condition and if my attending physician has determined that there can be no recovery from such condition and that my death is imminent, I direct that life-prolonging procedures be withheld or withdrawn when the application of such procedures would serve only to prolong artificially the process of dying.

In addition, Mrs. Browning stipulated that she desired not to have "nutrition and hydration (food and water) provided by gastric tube or intravenously."

At eighty-six years of age, Mrs. Browning suffered a stroke. She was admitted to the hospital on November 9, 1986, where her treating physician diagnosed a massive hemorrhage in the left parietal region of the brain, the portion that controls cognition. Because Mrs. Browning was unable to swallow, she underwent a gastrostomy on November 20 during which a feeding tube was inserted directly into her stomach.

The following day, she was discharged from the hospital and transferred to a nursing home where she remained bedridden and required total care. Mrs. Browning's second cousin and only living relative, Doris Herbert, eighty, was then appointed guardian of the person and property of Mrs. Browning.

During the course of her stay in the nursing home, Mrs. Browning was plagued with physical difficulties, including complications with her feeding tube, which became dislodged. The gastrostomy tube was replaced by a nasogastric tube on May 19, 1988.

Nearly two years after Mrs. Browning suffered her stroke, the guardian filed a petition in circuit court to terminate the nasogastric feeding based upon Mrs. Browning's living will. At the evidentiary hearing, the guardian presented additional evidence of Mrs. Browning's wishes. The evidence reflected that a predecessor living will, written in 1980, contained the same provisions for rejection of medical treatment at issue as the one presently before the Court. Believing that the death of a witness to the 1980 will might have rendered the will invalid, she executed the 1985 document. Neighbors also testified that Mrs. Browning had expressed her wishes orally in this regard several times. Mrs. Rose Kings, a close personal friend of Mrs. Browning since 1965, witnessed Mrs. Browning execute the 1985 document. She testified that Mrs. Browning signed the declaration about two days after visiting patients in a nursing home and had said, "`Oh Lord, I hope this never happens to me . . . thank God I've got this taken care of. I can go in peace when my time comes.'" Mrs. Kings' husband added that Mrs. Browning had a friend in the hospital on life-support and remarked that she "`never want[ed] to be that way.'"

The guardian, Mrs. Herbert, who had lived with Mrs. Browning from 1982 to 1986, testified that she had discussed the withdrawal of life-prolonging measures with Mrs. Browning following the death of Mrs. Browning's husband in 1978. According to Mrs. Herbert, Mrs. Browning said that she did not want to be maintained through artificial life-support mechanisms.

The consensus of the medical evidence indicated that the brain damage caused by the hemorrhage was major and permanent and that there was virtually no chance of recovery. Death would occur within seven to ten days were the nasogastric feeding tube removed. However, Mrs. Browning's life could have been prolonged up to one year as long as she was maintained on the feeding tube and assuming the absence of infection.

At the same time, the medical evidence reflected that Mrs. Browning was not comatose. Although she was noncommunicative, she "appeared alert and would follow [a visitor] with her eyes." However, she "would not blink in any consistent pattern when asked to respond to simple questions[,] . . . would not follow any simple commands[, and] . . . would not look to the right or to the left on command." A nurse testified that Mrs. Browning had attempted to say a word on a few occasions, although she conceded that the words had not been clear and the speech was garbled.

Dr. James Barnhill, a neurologist, described Mrs. Browning as noncommunicative and essentially existing only by virtue of fluid and nutrition supplied by the feeding tube. Dr. Barnhill opined that she was in a persistent vegetative state, which he defined as the absence of cognitive behavior and inability to communicate or interact purposefully with the environment.

The trial court found that Mrs. Browning could continue to live for an indeterminate time with artificial sustenance but that death would result within four to nine days without it. Construing Florida's "Life-Prolonging Procedure Act," sections 765.01-.15, Florida Statutes (1987), the trial court concluded that death was not imminent, and it denied the petition.

The district court affirmed the trial court's decision that the termination of this treatment was not permitted by the statute. However, the district court held that Mrs. Browning was entitled to relief under our state constitution, which expressly recognized every citizen's basic right of privacy. Browning, 543 So.2d at 261. The district court then authorized the guardian to make the decision in accordance with procedures established in the opinion.

II. A COMPETENT PERSON'S RIGHT OF PRIVACY

We agree with the district court that chapter 765 of the Florida Statutes (1987) is not applicable to Mrs. Browning's situation. We also agree with the district court that Mrs. Browning's fundamental right of self-determination, commonly expressed as the right of privacy, controls this case.

Because the word "privacy" generally has been used in common parlance in its informational or disclosural sense, its broader meaning has been somewhat ignored. However, the concept of privacy encompasses much more than the right to control the disclosure of information about oneself. "Privacy" has been used interchangeably with the common understanding of the notion of "liberty," and both imply a fundamental right of self-determination subject only to the state's compelling and overriding interest. For example, privacy has been defined as an individual's "control over or the autonomy of the intimacies of personal identity," Gerety, Redefining Privacy, 12 Harv.C.R.-C.L.L. Rev. 233, 281 (1977); or as a "physical and psychological zone within which an individual has the right to be free from intrusion or coercion, whether by government or by society at large." Cope, To Be Let Alone: Florida's Proposed Right of Privacy, 6 Fla.St.U.L.Rev. 671, 677 (1978).

These components of privacy are the same as those encompassed in the concept of freedom, and, as recognized in In re T.W., 551 So.2d 1186 (Fla. 1989), are deeply rooted in our nation's philosophical and political heritage. See also Winfield v. Division of Pari-Mutuel Wagering, 477 So.2d 544 (Fla. 1985). In Florida, we have recognized that this fundamental right of privacy has been expressly enumerated in article I, section 23 of the Florida Constitution, which provides "an explicit textual foundation for those privacy interests inherent in the concept of liberty." Rasmussen v. South Fla. Blood Serv., Inc., 500 So.2d 533, 536 (Fla. 1987).

Thus, we begin with the premise that everyone has a fundamental right to the sole control of his or her person. As Justice Cardozo noted seventy-six years ago:

Every human being of adult years and sound mind has a right to determine what shall be done with his own body. . . .

Recognizing that one has the inherent right to make choices about medical treatment, we necessarily conclude that this right encompasses all medical choices. A competent individual has the constitutional right to refuse medical treatment regardless of his or her medical condition. Wons; accord Cruzan ex rel. Cruzan v. Director, Mo. Dep't of Health, ___ U.S. ___, 110 S.Ct. 2841, 2852, 111 L.Ed.2d 224 (1990) ("for the purposes of this case, we assume that the United States Constitution would grant a competent person a constitutionally protected right to refuse lifesaving hydration and nutrition"). The issue involves a patient's right of self-determination and does not involve what is thought to be in the patient's best interests.

More is involved in respect for self-determination than just the belief that each person knows what's best for him- or herself. . . . Even if it could be shown that an expert (or a computer) could do the job better, the worth of the individual, as acknowledged in Western ethical traditions and especially in Anglo-American law, provides an independent — and more important — ground for recognizing self-determination as a basic principle in human relations, particularly when matters as important as those raised by health care are at stake.

President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research, I Making Health Care Decisions 44-45 (1982).

Courts properly have regarded the subjective desires of competent adults to forego medical intervention as dispositive. As the California Court of Appeal wrote in the case of Elizabeth Bouvia:

She, as the patient, lying helplessly in bed, unable to care for herself, may consider her existence meaningless. She cannot be faulted for so concluding. If her right to choose may not be exercised because there remains to her, in the opinion of a court, a physician or some committee, a certain arbitrary number of years, months, or days, her right will have lost its value and meaning.

Who shall say what the minimum amount of available life must be? Does it matter if it be 15 to 20 years, 15 to 20 months, or 15 to 20 days, if such life has been physically destroyed and its quality, dignity and purpose gone? As in all matters lines must be drawn at some point, somewhere, but that decision must ultimately belong to the one whose life is in issue.

Likewise, this Court has honored the subjective choices of competent patients to refuse medical treatment. In Public Health Trust v. Wons, 541 So.2d 96 (Fla. 1989), we held that a competent, thirty-eight-year-old practicing Jehovah's Witness could exercise her constitutional right to refuse an emergency blood transfusion, without which her death was certain to follow shortly. We approved the opinion of the district court, which concluded that Mrs. Wons was entitled "to exercise her religious freedom and to lead her private life according to her own conscience." Wons v. Public Health Trust, 500 So.2d 679, 687 (Fla. 3d DCA 1987), approved, 541 So.2d 96 (Fla. 1989). Also, in Satz v. Perlmutter, 379 So.2d 359 (Fla. 1980), adopting 362 So.2d 160 (Fla. 4th DCA 1978), we held that a competent, seventy-three-year-old patient who was suffering from terminal, incurable amyotrophic lateral sclerosis, was entitled to remove a mechanical respirator, without which death would occur within a short time. Mr. Perlmutter complained that his life was "miserable," and at a bedside hearing he testified that his condition without the respirator "can't be worse than what I'm going through now." Satz, 362 So.2d at 161.

We conclude that a competent person has the constitutional right to choose or refuse medical treatment, and that right extends to all relevant decisions concerning one's health. Courts overwhelmingly have held that a person may refuse or remove artificial life-support, whether supplying oxygen by a mechanical respirator or supplying food and water through a feeding tube. We agree and find no significant legal distinction between these artificial means of life-support.

III. AN INCOMPETENT PERSON'S RIGHT OF PRIVACY

Having determined that a competent person has the constitutionally protected right to choose or reject medical treatment, we consider whether this right is lost or diminished by virtue of physical or mental incapacity or incompetence. We previously determined that it is not. In John F. Kennedy Memorial Hospital, Inc. v. Bludworth, 452 So.2d 921, 923 (Fla. 1984), this Court held that an incompetent person has the same right to refuse medical treatment as a competent person. Thus, our cases have recognized no basis for drawing a constitutional line between the protections afforded to competent persons and incompetent persons. Indeed, the right of privacy would be an empty right were it not to extend to competent and incompetent persons alike. In re Guardianship of Barry, 445 So.2d 365, 370 (Fla. 2d DCA 1984). As we have already stated:

The primary concern . . . is that this valuable right should not be lost because the noncognitive and vegetative condition of the patient prevents a conscious exercise of the choice to refuse further extraordinary treatment.

IV. ANOTHER MAY EXERCISE THE INCOMPETENT'S RIGHT TO FOREGO MEDICAL TREATMENT

The real issue before us is an extension of the one presented in Bludworth. When a person is unable to personally and directly express his or her desires for health care because of physical and mental incapacity, "[t]he question is who will exercise this right and what parameters will limit them in the exercise of this right." Bludworth, 452 So.2d at 924-25. In Bludworth, the question related to a comatose patient. Mrs. Browning, in comparison, was not in a total comatose state. However, we fail to see a significant legal distinction. As we previously noted, the right involved here is one of self-determination that cannot be qualified by the condition of the patient. In this case, as in Bludworth, the patient was unable to personally or directly exercise the right to refuse medical treatment. Significantly, the patients in both cases, while competent, had executed written documents expressing their wishes.

We find that the district court correctly followed the principles underlying Bludworth. We hold that, because Mrs. Browning was unable to exercise her constitutional right of privacy by reason of her medical condition, her guardian was authorized to exercise it for her. As in Bludworth, we do not limit the ability to exercise this right only to a legally appointed guardian, but recognize that it may be exercised by proxies or surrogates such as close family members or friends. We emphasize and caution that when the patient has left instructions regarding life-sustaining treatment, the surrogate must make the medical choice that the patient, if competent, would have made, and not one that the surrogate might make for himself or herself, or that the surrogate might think is in the patient's best interests. As the court below aptly noted:

[I]t is important for the surrogate decisionmaker to fully appreciate that he or she makes the decision which the patient would personally choose. In this state, we have adopted a concept of "substituted judgment." [ In re Guardianship of Barry, 445 So.2d 365, 370-71 (Fla. 2d DCA 1984)]. One does not exercise another's right of self-determination or fulfill that person's right of privacy by making a decision which the state, the family, or public opinion would prefer. The surrogate decisionmaker must be confident that he or she can and is voicing the patient's decision.

The Ethics and Advocacy Task Force, as amicus curiae, raises a very legitimate concern that the "right to die" could become a license to kill. There are times when some people believe that another would be "better off dead" even though the other person is still fighting vigorously to live. Euthanasia is a crime in this state. § 782.08, Fla. Stat. (1987). See § 765.11(1), Fla. Stat. (1987). Despite the tremendous advances achieved in this century, the world has witnessed the extermination of retarded and mentally disturbed persons for whom a foreign government decided that death was the proper prescription. Thus, it cannot be overemphasized that the remedy announced in this opinion and the procedures designed to safeguard that remedy are based upon the patient's right to make a personal and private decision and not upon other interests.

The state argues that we should not permit the enforcement of Mrs. Browning's expressed wish because we can never know whether Mrs. Browning may have changed her mind. A critical problem regarding the exercise of an incompetent's choice is sometimes posed by the inability of the incompetent to express his or her immediate wishes. Unfortunately, human limitations preclude absolute knowledge of the wishes of someone in Mrs. Browning's condition. However, we cannot avoid making a decision in these circumstances, for even the failure to act constitutes a choice. That choice must be the patient's choice whenever possible. The right of privacy requires that we must safeguard an individual's right to chart his or her own medical course in the event of later incapacity.

V. COMPELLING STATE INTEREST

The state has a duty to assure that a person's wishes regarding medical treatment are respected. That obligation serves to protect the rights of the individual from intrusion by the state unless the state has a compelling interest great enough to override this constitutional right. The means to carry out any such compelling state interest must be narrowly tailored in the least intrusive manner possible to safeguard the rights of the individual.

Cases decided by this Court have identified state interests in the preservation of life, the protection of innocent third parties, the prevention of suicide, and maintenance of the ethical integrity of the medical profession, and have balanced them against an individual's right to refuse medical treatment.

The state's interest in the preservation of life generally is considered the most significant state interest. However, "`there is a substantial distinction in the State's insistence that human life be saved where the affliction is curable, as opposed to the State interest where, as here, the issue is not whether, but when, for how long and at what cost to the individual [his] [or her] life may be briefly extended.'" Satz v. Perlmutter, 362 So.2d 160, 162 (Fla. 4th DCA 1978) (quoting Superintendent of Belchertown State School v. Saikewicz, 373 Mass. 728, 740-44, 370 N.E.2d 417, 425-26 (1977)), adopted, 379 So.2d 359 (Fla. 1980). Hence, in Satz, we determined that a competent person suffering from an incurable affliction could refuse medical treatment. See also Wons. Likewise, in Bludworth, the state interests were insufficient to override the decision of a guardian or close family members carrying out the wishes of an incompetent patient not to be kept alive through the use of life-sustaining measures. Bludworth, 452 So.2d at 926.

Two other asserted state interests do not merit much discussion. First, there is no issue in this case pertaining to third parties. Second, suicide is not an issue when, as here, the discontinuation of life support "in fact will merely result in [her] death, if at all, from natural causes." Satz, 362 So.2d at 162.

The last and least significant of the aforementioned state interests is the maintenance of ethical integrity of the medical profession. However, "[r]ecognition of the right to refuse necessary treatment in appropriate circumstances is consistent with existing medical mores; such a doctrine does not threaten either the integrity of the medical profession, the proper role of hospitals in caring for such patients[,] or the State's interest in protecting the same." Satz, 362 So.2d at 163 (quoting Saikewicz, 373 Mass. at 742-45, 370 N.E.2d at 426-27). "Given the fundamental nature of the constitutional rights involved, protection of the ethical integrity of the medical profession alone could never override those rights." Wons, 541 So.2d at 101 (Ehrlich, C.J., concurring specially).

As we noted in Wons, the state interests discussed above are "by no means a bright-line test, capable of resolving every dispute regarding the refusal of medical treatment. Rather, they are intended merely as factors to be considered while reaching the difficult decision of when a compelling state interest may override the basic constitutional right of privacy." Wons, 541 So.2d at 97. We are satisfied that the state's interests do not outweigh the right of the individual to forego life-sustaining measures.

VI. PROCEDURES FOR THE DECISION-MAKER

The state argues that its interests are substantial enough to require more procedural protections than those provided in the district court's opinion. The state urges us to quash that section of the district court's opinion that permits a surrogate to make this life-or-death decision in a "private setting." Instead, the state suggests that we implement a judicial procedure requiring the surrogate to obtain prior court approval, giving an opportunity for the state or interested parties to be heard.

We cannot ignore the possibility that a surrogate might act contrary to the wishes of the patient. Yet, we are loath to impose a cumbersome legal proceeding at such a delicate time in those many cases where the patient neither needs nor desires additional protection. The decision to terminate artificial life-sustaining measures is being made over and over in nursing homes, hospitals, and private homes in this nation. It is being made painfully by loving family members, concerned guardians, or surrogates, in conjunction with the advice of ethical and caring physicians or other health care providers. It is being made when the only alternative to a natural death is to artificially maintain a bare existence. See In re Guardianship of Barry, 445 So.2d 365, 371 (Fla. 2d DCA 1984).

We are persuaded that when the patient has taken the time and the trouble to specifically express his or her wishes for future health care in the event of later incapacity, the surrogate need not obtain prior judicial approval to carry out those wishes. This applies whether the patient has expressed his or her desires in a "living will," through oral declarations, or by the written designation of a proxy to make all health care decisions in these circumstances. We recognize that instructions evinced in the form of a "living will" or other written or oral statements may not have designated a decision-maker to carry out those instructions. In instances when a patient has left instructions, the patient may designate, orally or in writing, the decision-maker who is to carry out those instructions; but the patient need not do so. However, when the patient has not expressed instructions, but has merely delegated full responsibility to a proxy, the designation of the proxy must have been made in writing.

A surrogate must take great care in exercising the patient's right of privacy, and must be able to support that decision with clear and convincing evidence. Before exercising the incompetent's right to forego treatment, the surrogate must satisfy the following conditions:

1. The surrogate must be satisfied that the patient executed any document knowingly, willingly, and without undue influence, and that the evidence of the patient's oral declarations is reliable;

2. The surrogate must be assured that the patient does not have a reasonable probability of recovering competency so that the right could be exercised directly by the patient; and

3. The surrogate must take care to assure that any limitations or conditions expressed either orally or in the written declaration have been carefully considered and satisfied.

Likewise, when a proxy has been designated to make the decision without explicit instructions from the patient, the proxy must satisfy the following conditions:

1. The proxy must be satisfied that the patient executed the written designation of proxy knowingly, willingly, and without undue influence; and

2. The proxy must be assured that the patient does not have a reasonable probability of recovering competency so that the right could be exercised directly by the patient.

In determining whether the patient may recover competency or whether a medical condition or limitation referred to in the declaration exists, the surrogate or proxy must obtain, and may rely upon, certificates from the patient's "primary treating physician" and "at least two other physicians with specialties relevant to the patient's condition." Bludworth, 452 So.2d at 926.

VII. CHALLENGES TO THE DECISION

We emphasize, as did the district court, that courts are always open to adjudicate legitimate questions pertaining to the written or oral instructions. First, the surrogate or proxy may choose to present the question to the court for resolution. Second, interested parties may challenge the decision of the proxy or surrogate.

When the decision of a proxy or surrogate is challenged, a written declaration or designation of proxy, in the absence of any evidence of intent to the contrary, establishes a rebuttable presumption that constitutes clear and convincing evidence of the patient's wishes. Evidence of the physicians' certificates establishing the existence of any medical condition required by the declaration likewise establishes a rebuttable presumption that these conditions have been satisfied.

Although a surrogate may rely on oral statements made by the incompetent, while competent, to exercise the incompetent's wishes to forego life-sustaining treatment, the presumption of clear and convincing evidence that attaches to a written declaration does not attach to purely oral declarations. Oral evidence, considered alone, may constitute clear and convincing evidence. However, the surrogate would bear the burden of proof if a decision based on purely oral evidence is challenged.

Because the only issue before the court is a determination of the patient's wishes, challenges generally would be limited to that issue. For example, there may be challenges to claims that the declaration was not executed knowingly, willingly, and without undue influence; that the patient had changed his or her mind after executing the declaration; that the declaration was ambiguous; that the conditions or limitations contained in the declaration were not satisfied; that the surrogate or proxy was the one actually designated; and, of course, that there was a reasonable probability that the patient would regain competency. When the only evidence of intent is an oral declaration, the accuracy and reliability of the declarant's oral expression of intent also may be challenged.

For example, Mrs. Browning made a written declaration. Had Mrs. Browning merely indicated in her written document that she wanted to refuse any and all efforts to artificially prolong her life, viable challenges to her guardian's decision to implement those wishes would have included: that Mrs. Browning changed her mind; that she executed the document unknowingly, unwillingly, or under undue influence; or that there existed a reasonable probability that she would regain competency. Evidence on other issues generally would have been irrelevant to the only issue to be decided — the patient's wishes.

In this instance, however, Mrs. Browning's wishes were conditional. She indicated that her decision to refuse treatment was limited to a time when she had a "terminal condition" from which her attending physician determined that there could be "no recovery" and that "death [was] imminent." Thus, in a case like this one, the surrogate's conclusions as to those matters could become additional bases of challenge. We are satisfied in this case that the surrogate's conclusions were correct. No one questioned that the declaration was executed by Mrs. Browning knowingly, willingly, and without undue influence. Nor was there any question that Mrs. Browning was beyond hope of regaining her competency and making the decision herself. Thus, the only question was whether the conditions established by Mrs. Browning in her declaration were satisfied.

The trial court found that death would occur within four to nine days after removal of the nasogastric tube. Therefore, Mrs. Browning's life could only have been sustained beyond that time by the administration of artificial, intrusive medical measures. Under those circumstances, Mrs. Browning's death was imminent as we construe her express written intent. In addition, all the doctors agreed that Mrs. Browning suffered permanent brain damage and the medical testimony established that there was no hope that she would recover from her condition. We are satisfied that clear and convincing evidence existed to support a finding that Mrs. Browning suffered from a terminal condition. Under these circumstances, the surrogate was correct in instructing Mrs. Browning's health care providers to discontinue all life-sustaining procedures in accordance with Mrs. Browning's wishes.

VIII. CONCLUSION

We have previously held that competent and incompetent persons have the right to determine for themselves the course of their medical treatment. Today we hold that, without prior judicial approval, a surrogate or proxy, as provided here, may exercise the constitutional right of privacy for one who has become incompetent and who, while competent, expressed his or her wishes orally or in writing. We also determine that there is no legal distinction between gastrostomy or nasogastric feeding and any other means of life support. This case resolves a question of an individual's constitutional right of self-determination. We are hopeful that this decision will encourage those who want their wishes to be followed to express their wishes clearly and completely.

For the reasons expressed above, we answer the certified question in the affirmative as qualified here and approve the decision of the district court.

It is so ordered.

SHAW, C.J., and EHRLICH, GRIMES and KOGAN, JJ., concur.

McDONALD, J., concurs with an opinion.

OVERTON, J., concurs in part and dissents in part with an opinion.