 abduction |  Carnap, Rudolf |  conditionals |  confirmation |  creationism |  dispositions |  essential vs. accidental properties |  Goodman, Nelson |  Kuhn, Thomas |  laws of nature |  Popper, Karl |  probability, interpretations of |  Quine, Willard Van Orman |  Reichenbach, Hans |  science: theory and observation in |  scientific explanation 