If yes, what kind of god was man indebted to? To a god who once drowned the whole of mankind except one family? To a god who said that he was a jealous being who "visited the sins of the father upon the children unto a third and fourth generation." (Ex. xx., 5)? To a god who sanctioned slavery (Lev. xxv., 44, 45) and injustice of all kinds? To a god who said "thou shalt not suffer a witch to live" (Ex. xxii., 18), and gave instructions for men to kill the blasphemers among their fellows (Lev. xxiv., 16)? To a god who told Moses to go against the Midianites and slay every man among them, preserving only the virgins among the women to satisfy the lustful natures of a brutal horde of soldiers (Numbers xxxi., 7--18)? To a god to whom, as Shelley says, the only acceptable offerings were "the steam of slaughter, the dissonance of groans, and the flames of a desolate land" (Dialogue between "Eusebes and Theosophus," prose writings, page 300)? I deny that man has ever been in any way indebted to such a god, and I say moreover that such a deity never had any real existence, except in the base imaginations of ignorant and brutal men. But the next stage was from the material to the spiritual god. Many ages must have elapsed before this more elevating though equally absurd belief became to be accepted, even by a small minority of mankind. But the time eventually did come--a time which happily is now rapidly passing away--when intellectual men believed that the proposition of the existence of god could be demonstrated to all rational minds. Some said that god's existence was self-evident to every intelligent mind; others that Nature and men could not have come by "chance"; that they must have had a cause; some said that the harmony existing in the universe proved god's existence; others that everybody except fools "felt in their hearts" that there was a god. But these imaginary proofs did not always convince. At last there came forth philosophers who said that there was a mode of reasoning, the adoption of which "leads irresistibly up to the belief in god," and that that mode was called the mode _à priori_. Another school said that the _à priori_, or reasoning from cause to effect, was an altogether fallacious method, and that the only satisfactory mode of establishing god's existence was the _à posteriori_, or reasoning from effect to cause. Another school said that taken singly neither of these modes of reasoning established the existence of deity, but that both taken together "formed a perfect chain" of reasoning that was quite conclusive on the point. Neither of these schools, however, showed how two bad arguments could possibly make one good one. But let me just briefly examine these arguments put forward so confidently by leading Theists. The first method--_à priori_--invariably takes the form of an attempt to establish what is called a "Great First Cause."