TY JOUR TI the meaning of the Ernst Haeckel’s monism in the history of philosophy KW philosophy of the late nineteenth and early twentieth centuries KW Ernst Haeckel KW monism KW darwinism KW pantheism KW natural-science materialism KW atheism KW consciousness KW ether KW the law of substance JO Journal of Philosophical Research AU Kudrin, S.K. PY 2019 IS 5 PB INFRA-M Academic Publishing LLC.