20 Pa. C.S. § 7213
The rules of this chapter are standards of conduct and not of outcome or performance. Compliance with the rules of this chapter shall be determined in light of the facts and circumstances prevailing at the time of the fiduciary's decision or action and not by hindsight. A fiduciary is not liable to the extent the fiduciary acted in substantial compliance with the rules of this chapter or in reasonable reliance on the terms and provisions of the governing instrument. A fiduciary's investment and management decisions respecting individual assets shall be considered in the context of the trust portfolio as a whole and as part of an overall investment strategy, and not in isolation. No specific investment or course of action, taken alone, shall be considered inherently prudent or imprudent.
20 Pa.C.S. § 7213