This chapter analyzes Stages on Life’s Way as an extended thought experiment. Though it has some similarities with a literary work of art and is sometimes called a novel, I distinguish extended thought experiment narratives like Stages from literary novels. I will show how Stages, like Repetition, embodies and develops Ørsted’s core elements of variation, active constitution, and the pursuit of genuine thought. I will also contrast Stages as a “psychological experiment” with the field of empirical psychology emerging in the 1800s. Against increasing interest in empirical observation, Kierkegaard’s thought experiments direct attention to what is not outwardly observable.

Neurons generate electromagnetic fields as they communicate with each other. Chapter 9 introduces the electromagnetic field as a key concept overarching different electrophysiological brain activities. The concept corrects common misconceptions (e.g. "EEG is the sum of action potentials") and provides a common basis for data analysis of field signals. Basic properties of the field signal, amplitude, phase and frequency, are explained in plain language.

In addition, two major noninvasive techniques for measuring field activity, electroencephalography (EEG) and magnetoencephalography (MEG), are introduced. The advantages and disadvantages of the methods are discussed with a brief history of the techniques.

This method explains in an accessible way what the underlying principles are of magnetic resonance imaging, which underlies all structural imaging methods that are described in the next chapter.

This chapter sets the stage. We provide several examples of how neuroimaging findings have been covered in popular media, and the criticism that such coverage has elicited. This book intends to provide the knowledge and facts to understand the potential and proper use and mis-use of neuroimaging methods. We end with a brief overview of the different types of neuroimaging methods, and how they are organized with respect to spatial resolution, temporal resolution, and level of invasiveness.

We provide an introduction in the main pre-processing steps that are involved when analyzing imaging data: Correction for slice timing, motion correction, coregistration, normalization, and spatial smoothing

We discuss three more advanced statistical analysis approaches. First, the analysis of functional connectivity, including topics like directional and effective functional connectivity, modulations of connectivity by task (psychophysiological interactions), and resting-state fMRI. Second, we cover multivariate analyses and multi-voxel pattern analyses, and we discuss their potential and limitations to understand information processing in the brain. Third, we introduce the use of functional MRI adaptation as a means to measure neural selectivity.

Chapter 12 covers selected advanced data analysis methods for EEG and MEG data. In time-frequency analysis, two relevant techniques, the Short Time Fourier Transform (STFT) and the Wavelet Transform (WT), are explained in a flat language.

Phase analysis begins with the calculation of phase, which is made easy with graphical representations. The nature of the phase signal is explained using simple circular statistics. This makes phase synchronization and functional network analysis easy to understand.

In addition, event-related analysis of phase signals (Inter-trial Phase Coherence) is introduced to complete the family of event-related brain response analyses.

In addition to correlation-based phase synchronization analysis, autoregression analysis is introduced as a method of causality inference.

This chapter explains the physical and biological principles behind the main imaging methods that measure hemodynamics, including Blood-oxygenation-level-dependent (BOLD) functional MRI, arterial spin labeling fMRI, positron emission tomography (PET), and functional near-infrared spectroscopy (fNIRS). Molecular neuroimaging is also covered in the discussion of PET and MRS.

The conclusion outlines key points in the book. On a Kantian-Kierkegaardian account, thought experiments lead to presentations that justify calling a thought experiment an experience, though not an empirical or sensory one. Without a sensible object, we can nevertheless have givenness, or presence, but not existence. Cognition, for that reason, is not necessarily truthful: although object-directed, cognition on its own does not justify belief in any particular object’s existence. My conclusion that thought experiments provide cognition rather than knowledge echoes Michael Stuart’s claim that thought experiments increase understanding. Cognition is a common basis for knowledge in Kant, but it is not the same thing as knowledge. The conclusion also draws implications for how we understand faith (religious belief) in Kierkegaard and how thought experiments make sense of the complexity of reality.

Rationalist accounts of thought experiment in epistemology offer an alternative to the more predominantly empiricist approaches in philosophy of science. In this chapter, I will pose a Kantian critique of recent rationalist accounts of intellectual intuition. Some epistemologists have recently argued that intellectual intuitions can provide prima facie justification for judgments. In this chapter, I highlight some promising elements of recent rationalist accounts, especially the proposal that there can be nonsensory presentations analogous to empirical perceptions. If they are right, then thought experiments can provide new experiential content even without empirical confirmation. However, I also draw attention to Kant’s objections to the possibility of purely intellectual intuitions.

Kierkegaard and Ørsted were not just contemporaries but personally knew each other. In this chapter, I argue that Kierkegaard probably learned the term Tankeexperiment from Ørsted. This chapter contextualizes Kierkegaard’s use of “imaginary construction” (Experiment) in his work as a whole, including his well-known uses of paradoxes. I will show how the core elements of Ørsted’s account – thought experiment as a method of variation, the need for free and active constitution, and the use of thought experiments for facilitating genuine thought – are echoed in Kierkegaard’s discussions. Along the way, I will describe some decisions on how to translate Experiment and Tankeexperiment that are unfortunate in some ways and fortuitous in others, as I will explain. In these ways, Kierkegaard indirectly takes up Kant’s proposal that “construction” (i.e., Experiment in Danish) is a means of achieving cognition.