Next to these we may place those who suffer their own natural tempers and passions they are possessed with to influence their judgments,especially of men and things that may any way relate to their present circumstances and interest.Truth is all ******,all pure,will bear no mixture of anything else with it.It is rigid and inflexible to any by-interests;and so should the understanding be,whose use and excellency lies in conforming itself to it.To think of everything just as it is in itself is the proper business of the understanding,though it be not that which men always employ it to.
This all men,at first hearing,allow is the right use everyone should make of his understanding.Nobody will be at such an open defiance with common sense as to profess that we should not endeavor to know and think of things as they are in themselves,and yet there is nothing more frequent than to do the contrary;and men are apt to excuse themselves,and think they have reason to do so,if they have but a pretense that it is for God or a good cause,that is,in effect,for themselves,their own persuasion or party;for those in their turns the several sects of men,especially in matters of religion,entitle God and a good cause.
But God requires not men to wrong or misuse their faculties for him,nor to lie to others or themselves for his sake;which they purposely do who will not suffer their understandings to have right conceptions of the things proposed to them and designedly restrain themselves from having just thoughts of everything,as far as they are concerned to enquire.And as for a good cause,that needs not such ill helps;if it be good,truth will support it and it has no need of fallacy or falsehood.