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 speculators to recur; when they have undertaken to reconcile the spirituality of the soul, with the physical action of material beings, on this incorporeal substance; its re-action upon these beings; its union with the body. When the human mind permits itself to be guided by authority without proof, to be led forward by enthusiasm; when it renounces the evidence of its senses; what can it do more than sink into error? Let those who doubt this, read the metaphysical romances of LEIBNITZ, DESCARTES, MALEBRANCHE, CUDWORTH, and many others: let them coolly examine the ingenious, but fanciful systems entitled the pre-established harmony of occasional causes; physical pre-motion, &amp;c.

If man wishes to form to himself clear, perspicuous ideas of his soul, let him throw himself back on his experience&mdash;let him renounce his prejudices&mdash;let him avoid theological conjecture&mdash;let him tear the bandages which he has been taught to think necessary, but with which he has been blind-folded, only to confound his reason. If it be wished to draw man to virtue, let the natural philosopher, let the anatomist, let the physician, unite their experience; let them compare their observations, in order to show what ought to be thought of a substance, so disguised, so hidden by absurdities, as not easily to be known. Their discoveries may perhaps teach moralists the true motive-power that ought to influence the actions of man&mdash;legislators, the true motives that should actuate him, that should excite him to labour to the welfare of society&mdash;sovereigns, the means of rendering their subjects truly happy; of giving solidity to the power of the nations committed