Shepherd vol 2 ebook: Chapter 11: Experimentum Crucis in Shepherd's 1824 Treatise

Chapter 11: Experimentum Crucis in Shepherd's 1824 Treatise

In my previous chapter, I looked at where Mary Shepherd used this Latin term for a Crucial Experiment in her 1827 treatise 'Essays on the Perception of an External Universe'¹. In this third and last chapter dedicated to the methodology of Experimentum Crucis, I shall explore the passages in which she discusses Experimentum Crucis within her earlier treatise, published in 1824, titled: 'An Essay upon the Relation of Cause and Effect’².  

Earlier on, in her treatise: ‘Essays upon the Relation of Cause and Effect’, Shepherd argues:

“The very meaning of the word Cause, is Producer or Creator; of Effect, the Produced or Created and the idea is gained by such an observance of nature, as we think is efficient in any given case, to an experimentum crucis."³

Here, Shepherd bases her claim (that Cause, Producer and Creator are like synonyms in that they share the same meaning) on scientific methodology not scripture, such as, observing nature in a way which can lead to a crucial experiment that helps us pick out what is the cause and what is the effect. Hence, we see that Shepherd thinks that a rigorous experiment, based on scientific observations of the natural world, is a standard by which to judge the strength of our theories, and decide what can be proved, and what is left undecided⁴. Elsewhere in passages of these Treatises⁵, Shepherd leaves open the possibility of the existence of an immaterial soul or spirit, not to be pious, but because science seems to struggle to explain the difference between being conscious and not being conscious. The word soul rarely turns up in her Treatises⁶ and she hardly ever talks about it in its own right as a religious concept, for instance, she never says that post death the soul goes to heaven. Shepherd tends to speak of soul and mind in one breath⁷.

Indeed, in both her 1824 and 1827 treatises⁸, Shepherd barely mentions scripture and when she does, it is very brief, only in passing, and it does not seem to be of great influence in and of itself. 

For example, in her ‘Essays on the Perception of an External Universe’⁹, when she discusses her own personal approach, she does not base her logical inferences on scripture but instead prefers to focus on whether something poses a philosophical problem: 

"As for myself, though I think that, independant of the inference from scripture, the reunion of memory to future consciousness presents no philosophical difficulty”.¹⁰

And on the next page, she writes: 

"—that an instinctive devotion towards God should meet with higher demonstrations of his presence than our faint conceptions here are able to embrace"¹¹

This, I argue, perhaps shows that Shepherd does not uphold irrational, unquestioning blind faith, but thinks any faith in God should be backed up by demonstrations of His presence, not some feeble notions of a God. 

For comparison, in her 'Essays upon the Relation of Cause and Effect’, Shepherd argues: 

"Long observation of the invariableness of antecedency, and subsequency, is not wanted; many trials are not wanted, to generate the notion of producing power.

One trial is enough, in such circumstances, as will bring the mind to the following reasoning.”¹²

Here I think we can see Shepherd valuing one crucial experiment to prove something, over many, drawn out observations to assess whether A is invariably followed by B to figure out the causes and effects at play. 

So I suggest that Experimentum Crucis is not just for practical science experiments, it is also a methodology that is vital for understanding philosophers who equally draw upon it, especially metaphysicians and natural philosophers. 

Furthermore, I suggest that the passage on page 43 of Shepherd’s ‘Essays upon the Relation of Cause and Effect’ treatise¹³ pairs with another one later on in the same treatise. In this later passage, Shepherd¹⁴ is still dealing with the topics of Cause and Effect and how she feels she can support her theory in one blow, through the methodological approach of Experimentum Crucis over other competing explanations and theories. For instance, constant conjunction needs to laboriously study whether B always follows A, in order to conclude with some confidence that A is the cause of B. Nevertheless, as Shepherd argues, this may be an oversimplification that may lead us into oversights or errors¹⁵. 

I maintain that the textual evidence for this can be seen when Shepherd writes: 

“I have endeavoured to show, that any one junction of bodies in fit circumstances for what is termed the experimentum crucis, may be sufficient to establish where the power lies towards the production of certain qualities, that ordinary life affords such experiment to the mind; and that without it, constant conjunctions of antecedent and subsequent objects, will not prove where the Cause of an Effect is. Conjunctions, however frequent, may be separable both in fact and fancy; Cause and Effect, a changed object with its changed qualities, are inseparable in both.”¹⁶

Hence, I suggest, the method and approach of Experimentum Crucis is vital to understanding Shepherd's philosophy, theories and her views on causation. In this passage¹⁷, we again see that Shepherd concludes that she has tried to show that an Experimentum Crucis is sufficient to discover the cause and effect being analysed. Furthermore, for Shepherd, an Experimentum Crucis will unearth the cause and effect we are examining, better than the method of looking for frequent occurrences of constant conjunctions. 

So, putting these two Experimentum Crucis passages¹⁸ together from her 1824 treatise, Shepherd’s approach is that ideas are gained by observing nature which point us to conducting an experimentum crucis to turn our ideas into solid, true, hard or impossible to refute theories about the world. Hence, for Shepherd, I think we have to appreciate that, when she seems to support the idea of the existence of God, she is not doing so as a result of following religious doctrine or part of leading a religious life. She has scientific and rational reasons behind supporting the existence of God.

References:

¹Shepherd, Mary. Essays on the Perception of an External Universe and Other Subjects Connected with the Doctrine of Causation, 1st edition 

(Piccadilly, London, United Kingdom: J. Hatchard and son, 1827), 

http://archive.org/details/essaysonpercepti00shep. 

²Shepherd, Mary. An Essay upon the Relation of Cause and Effect : Controverting the Doctrine of Mr. Hume, Concerning the Nature of That Relation, with Observations upon the Opinions of Dr. Brown and Mr. Lawrence Connected with the Same Subject (London, United Kingdom: Printed for T. Hookham, 1824), http://archive.org/details/essayuponrelatio00shepiala 

³Ibid p43

⁴Shepherd, An Essay upon the Relation of Cause and Effect 

⁵Shepherd, Essays on the Perception of an External Universe; Shepherd, An Essay upon the Relation of Cause and Effect 

⁶Ibid

⁷Ibid

⁸Ibid

⁹Shepherd, Essays on the Perception of an External Universe 

¹⁰Ibid p384 

¹¹Ibid p385

¹²Shepherd, Essays upon the Relation of Cause and Effect, p43 

¹³Ibid

¹⁴Shepherd, Essays upon the Relation of Cause and Effect

¹⁵Ibid

¹⁶Ibid p1

93

¹⁷Ibid

¹⁸Shepherd, Essays upon the Relation of Cause and Effect, p43; p193