In every chain of reasoning, the evidence of the last conclusion can be no greater than that of the weakest link of the chain, whatever may be the strength of the rest.
Thomas ReidEvery indication of wisdom, taken from the effect, is equally an indication of power to execute what wisdom planned.
Thomas ReidIt appears evident, therefore, that those actions only can truly be called virtuous, and deserving of moral approbation, which the agent believed to be right, and to which he was influenced, more or less, by that belief.
Thomas Reid