In Cooper v Slade (1858), 6 HL Cas 746, Willes J said at p 772:
As a difference of opinion exists upon this question, I may be excused for referring to an authority in support of the elementary proposition that in civil cases the preponderance of probability may constitute sufficient ground for a verdict. … So long since as the 14 Eliz., DYER CJ, and a majority of the other justices of the Common Pleas laid down this distinction between pleadings and evidence, 'that in a writ or declaration or other pleading certainty ought to be shown, for there the party must answer to it, and the court must adjudge upon it; and that which the party shall be compelled to answer to, and which is the foundation whereupon the court is to give judgment, ought to be certain, or else the party would be driven to answer to what he does not know and the court to give judgment upon that which is utterly uncertain. But where the matter is so far gone that the parties are at issue, or that the inquest is awarded by default, so that the jury is to give a verdict one way or the other, there, if the matter is doubtful, they may found their verdict upon that which appears the most probable, and by the same reason that which is most probable shall be good evidence'.
In Miller v Minister of Pensions  2 All ER 372 Denning J summarized requirements for the standard of proof to convict the accused in a criminal case, as below:
It need not reach certainty, but it must carry a high degree of probability. Proof beyond reasonable doubt does not mean proof beyond a shadow of a doubt. The law would fail to protect the community if it permitted fanciful possibilities to deflect the course of justice. If the evidence is so strong against a man as to leave only a remote possibility in his favour which can be dismissed with the sentence "Of course it is possible but not in the least probable", the case is proved beyond reasonable doubt; nothing short will suffice."
He then set the standard of proof for a civil case in the following words:
It must carry a reasonable degree of probability, not so high as is required in a criminal case. If the evidence is such that the tribunal can say: ‘we think it more probable than not’, the burden is discharged, but if the probabilities are equal it is not.
Denning LJ referred both to criminal and to civil cases again in Bater v Bater  2 All ER 458 at p 459:
The difference of opinion which has been evoked about the standard of proof in these cases may well turn out to be more a matter of words than anything else. It is true that by our law there is a higher standard of proof in criminal cases than in civil cases, but this is subject to the qualification that there is no absolute standard in either case. In criminal cases the charge must be proved beyond reasonable doubt, but there may be degrees of proof within that standard. Many great judges have said that, in proportion as the crime is enormous, so ought the proof to be clear. So also in civil cases. The case may be proved by a preponderance of probability, but there may be degrees of probability within that standard. The degree depends on the subject-matter. A civil court, when considering a charge of fraud, will naturally require a higher degree of probability than that which it would require if considering whether negligence were established. It does not adopt so high a degree as a criminal court, even when it is considering a charge of a criminal nature, but still it does require a degree of probability which is commensurate with the occasion.
Per Bucknill LJ in Gower v Gower  1 All ER 804 at 805:
The standard of proof required in a criminal case is higher than the standard of proof in a civil action because in a civil action a matter may be proved on a balance of probabilities and the court may decide one way or the other on a very small margin of preference, while, on the other hand, in a criminal case the matter must be proved beyond any reasonable doubt. To put it in another way, if the case for the prosecution is based on circumstantial evidence, the evidence must be such as to be inconsistent with any reasonable hypothesis other than the guilt of the accused. If the accused gives any reasonable explanation which is consistent with innocence, the matter is not proved beyond any reasonable doubt.
Bhandari v Advocates Committee  3 All ER 742 per Lord Tucker at 745:
In every allegation of professional misconduct involving an element of deceit or moral turpitude, it is the duty of the professional domestic tribunal investigating the allegations to apply a high standard of proof and not to condemn on a mere balance of probabilities.
Elaborated opinion was expressed by Morris LJ in Hornal v Neuberger Products Ltd  3 All ER 970 at p.978-979
In a criminal case a jury must be directed that the onus is all the time on the prosecution and that before they convict they must feel sure of the accused’s guilt. … It has, however, been emphasised that what is vital is not the mere using of some particular formula of words but the ef-fect of a summing-up in giving true guidance as to the right approach.
It is, I think, clear from the authorities that a difference of approach in civil cases has been recognised. Many judicial utterances show this. The phrase "balance of probabilities" is often employed as a convenient phrase to express the basis on which civil issues are decided. It may well be that no clear-cut logical reconciliation can be formulated in regard to the authorities on these topics; but perhaps they illustrate that "the life of the law is not logic but experience". In some criminal cases liberty may be involved; in some it may not. In some civil cases the issues may involve questions of reputation which can transcend in importance even questions of personal liberty. "Good name in man or woman … is the immediate jewel of their souls".
In truth no real mischief results from an acceptance of the fact that there is some difference of approach in civil actions. Particularly is this so if the words which are used to define that approach are the servants but not the masters of meaning. Though no court and no jury would give less careful attention to issues lacking gravity than to those marked by it, the very elements of gravity become a part of the whole range of circumstances which have to be weighed in the scale when deciding as to the balance of probabilities. This view was denoted by Denning LJ when in his judgment in Bater v Bater  2 All ER 458 at p 459 he spoke of a "degree of probability which is commensurate with the occasion" and of "a degree of probability which is proportionate to the subject-matter."
In English law the citizen is regarded as being a free man of good repute. Issues may be raised in a civil action which affect character and reputation, and these will not be forgotten by judges and juries when considering the probabilities in regard to whatever misconduct is alleged. There will be reluctance to rob any man of his good name: there will also be reluctance to make any man pay what is not due or to make any man liable who is not or not liable who is. A court will not be deterred from a conclusion because of regret at its consequences: a court must arrive at such conclusion as is directed by the weight and preponderance of the evidence.