Knowledge as a personal act: Newman on the understanding of reality
A central achievement of Newman is that of understanding that there is a personal element of judgement in every act of knowledge, in every act of assent to a proposition. Knowledge is not a passive process, or a mechanic process. Knowledge involves the whole of the self. No truth is self evident, every assent is based on the evaluation of a number of probabilities, and in this process the whole of the individual is involved. Certitude is a very personal choice: it involves choosing how many pieces of evidence you need to be certain about something, how many proofs you need to assent to a certain proposition. This number is highly variable and is influenced by a number of factors who fall outside the rational domain. The amount of evidence is never commensurate to the certitude we have in one thing. The lack of evidence is not necessary a sign of the falseness of a proposition, as there might be reasons which make this evidence unattainable. It follows that, for instance, the same series of events which seem to trespass human nature might be sufficient for one person to acknowledge the presence of the supernatural in the world, and not sufficient for another. As ideas on the borders of human nature vary, the same action can be attributed to divine presence by someone, or seen as human achievement by another:
“Recurring to Pascal's argument, I observe that, its force depending upon the assumption that the facts of Christianity are beyond human nature, therefore, according as the powers of nature are placed at a high or low standard, that force will be greater or less; and that standard will vary according to the respective dispositions, opinions, and experiences, of those to whom the argument is addressed. Thus its value is a personal question; not as if there were not an objective truth and Christianity as a whole not supernatural, but that, when we come to consider where it is that the supernatural presence is found, there may be fair differences of opinion, both as to the fact and the proof of what is supernatural. There is a multitude of facts, which, taken separately, may perhaps be natural, but, found together, must come from a source above nature; and what these are, and how many are necessary, will be variously determined. And while every inquirer has a right to determine the question according to the best exercise of his judgment, still whether he so determine it for himself, or trust in part or altogether to the judgment of those who have the best claim to judge, in either case he is guided by the implicit processes of the reasoning faculty, not by any manufacture of arguments forcing their way to an irrefragable conclusion.
JHN Grammar of Assent 8.2
http://www.newmanreader.org/works/grammar/chapter8-2.html
“Recurring to Pascal's argument, I observe that, its force depending upon the assumption that the facts of Christianity are beyond human nature, therefore, according as the powers of nature are placed at a high or low standard, that force will be greater or less; and that standard will vary according to the respective dispositions, opinions, and experiences, of those to whom the argument is addressed. Thus its value is a personal question; not as if there were not an objective truth and Christianity as a whole not supernatural, but that, when we come to consider where it is that the supernatural presence is found, there may be fair differences of opinion, both as to the fact and the proof of what is supernatural. There is a multitude of facts, which, taken separately, may perhaps be natural, but, found together, must come from a source above nature; and what these are, and how many are necessary, will be variously determined. And while every inquirer has a right to determine the question according to the best exercise of his judgment, still whether he so determine it for himself, or trust in part or altogether to the judgment of those who have the best claim to judge, in either case he is guided by the implicit processes of the reasoning faculty, not by any manufacture of arguments forcing their way to an irrefragable conclusion.
JHN Grammar of Assent 8.2
http://www.newmanreader.org/works/grammar/chapter8-2.html