Causes and Conditions - American Philosophical Quarterly, Vol. 2, No. 4

Asked what a cause is, we may be tempted to say that it is an event which precedes the event of which it is the cause, and is both necessary and sufficient for the latter's occurrence, briefly, that a cause is a necessary and sufficient preceding condition. There are, however, many difficulties in this account. I shall try to show that what we often speak of as a cause is a condition not of this sort, but of a sort related to this. That is to say, this account needs modification, and can be modified, and when it is modified we can explain much more satisfactorily how we can arrive at much of what we ordinarily take to be causal knowledge; the claims implicit within our causal assertions can be related to the forms of the evidence on which we are often relying when we assert a causal connection.