What does the word indubitable mean?

Usage examples for indubitable

  1. Such is the nature of the human mind, that we all begin in this sphere of equal knowledge, we begin under the dominion of the senses, and whatever comes within that wants no demonstration, wants no proof, wants no logic; it is the constant, it is the most indubitable, it is the most indisputable of all our knowledge. – Modern Atheism under its forms of Pantheism, Materialism, Secularism, Development, and Natural Laws by James Buchanan
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